I've flown >60k miles for the past 5 years. I've had my bags delayed exactly once, for a whopping 12hrs. The 5% is bullshit, 2005 domestic delayed/mishandled bag rate was .61% (roughly 6.1 bags per 1,000 passengers) - and Arch is on the money because >60% of that is mishandled transfer bags. Tight connections increase your odds of mishandling. People who carryon climbing gear (or ski boots, or any other nonbreakable) just want to look cool in the airport bar, take up binspace and fuck up boarding.